But with REAL stores, you can take the item or the receipt back the next day and tell them it just went on sale and they refund the difference.

This is done as a courtesy at best.

None of the stores I worked at would take merchandise that is on sale now and refund you the difference you pay. I currently work at a store where the return policy is a "30 day satisfaction guaranteed" one. So if there was a refunded difference, it would be because the associate realizes that you can merely return the product and then re-buy it.

And that even depends. Good luck trying to return half a roll of duct tape, or half a gallon of bleach.

So no, it's not that simple.

Sales are sales, and they happen when they happen. Tough shi- er.... cookies if you missed it.